Light emitting diodes (LEDs) are semiconductor-based light sources traditionally employed in low-power instrumentation and appliance applications for indication purposes and are available in a variety of colors (e.g., red, green, yellow, blue, white), based on the types of materials used in their fabrication. This color variety of LEDs has been recently exploited to create novel LED-based light sources having sufficient light output for new space-illumination and direct view applications. For example, as discussed in U.S. Pat. No. 6,016,038, incorporated herein by reference, multiple differently colored LEDs may be combined in a lighting fixture having one or more internal microprocessors, wherein the intensity of the LEDs of each different color is independently controlled and varied to produce a number of different hues. In one example of such an apparatus, red, green, and blue LEDs are used in combination to produce literally hundreds of different hues from a single lighting fixture. Additionally, the relative intensities of the red, green, and blue LEDs may be computer controlled, thereby providing a programmable multi-channel light source, capable of generating any color and any sequence of colors at varying intensities and saturations, enabling a wide range of eye-catching lighting effects. Such LED-based light sources have been recently employed in a variety of fixture types and a variety of lighting applications in which variable color lighting effects are desired. Lighting systems employing multiple such light sources, and the effects they produce, can be controlled and coordinated through a network, wherein a data stream containing packets of information representing lighting commands is communicated to the lighting devices. Each of the lighting devices may register all of the packets of information passed through the system, but only respond to packets that are addressed to the particular device. Once a properly addressed packet of information arrives, the lighting device may read and execute the lighting commands. Based on the network controllability of such lighting systems, lighting programs may be authored for these systems which, when executed, generate a wide variety of lighting effects or “lighting shows” in any of a number of different environments.
In general, a “lighting effect” refers to one or more states of light that are perceived as an entity over some period of time. A lighting effect may include a single color of light (including generally white light) or multiple colors of light perceived simultaneously and/or in some sequence. A lighting effect may have one or more static and/or dynamic characteristics, and exemplary dynamic characteristics may relate to one or more of color, brightness, perceived transition speed, perceived motion, periodicity, and the like. A “lighting show” may comprise a single lighting effect having some finite duration that is executed once, repeated periodically in some prescribed fashion, or repeated indefinitely. A lighting show also may comprise a number of different lighting effects executed in sequence or simultaneously according to a wide variety of definable parameters. Lighting effects constituting a lighting show also may be packaged as “meta-effects” that include multiple temporally linked lighting effects. One or more lighting effects, or an entire lighting show, may be based on parameters that are definable by a designer/programmer, or based at least in part on predefined (“pre-packaged”) lighting effects available for selection by the designer/programmer during the authoring process. Additionally, all or a portion of a lighting effect or lighting show may be based on graphics or animation data, as well as video signals, that are converted to lighting control information pursuant to designer/programmer instructions provided during the authoring process.
Lighting effects or lighting shows may be authored by a designer/programmer via a graphical user interface (GUI) coupled to one or more processors/computers which collectively serve as a “light system composer.” Exemplary methods and systems for authoring lighting effects or shows are discussed in U.S. Pat. No. 7,139,617, and U.S. Patent Application Publication No. US-2005-0248299-A1, both of which are incorporated herein by reference. As discussed in these references, a lighting effect or lighting show may be encoded as a sequential list of lighting states and transitions between lighting states, or frames of color data with reference to some time base, as a lighting program, which is then communicated to a lighting controller; the lighting controller in turn may be configured to generate lighting commands for execution by one or more lighting units based on the lighting program representing the lighting effect or lighting show.